Add Windows import library support to the Runtime Linker

Summary:
Import libraries are files ending in `.dll.a` and `.lib` depending on which
compiler creates them (GCC, vs MSVC).

Import Libraries are standard `archive` files that contain object files.
These object files can have two different formats:

1) The normal COFF Object format for object files
    (contains all ascii data and very little program code, so do not
     try to execute.)
2) "short import" format which just contains a symbol name and
   the dll in which the symbol can be found.

Import Libraries are useful for two things:

1) Allowing applications that don't support dynamic linking to
   link against the import lib (non-short format) which then
   makes calls into the DLL by loading it at runtime.

2) Allow linking of mutually recursive dlls. if `A.DLL` requires
   `B.DLL` and vice versa, import libs can be used to break the cycle
   as they can be created from the expected exports of the DLLs.

A side effect of having these two capabilities is that Import libs are often
used to hide specific versions of DLLs behind a non-versioned import lib.

e.g. GCC_S.a (non-conventional import lib) will point to the correct
`libGCC` DLL. With this support Windows Haskell files can now just link
to `-lGCC_S` and not have to worry about what the actual name of libGCC is.

Also third party libraries such as `icuuc` use import libs to forward to
versioned DLLs. e.g. `icuuc.lib` points to `icuuc51.dll` etc.

Test Plan:
./validate

Two new tests added T11072gcc T11072msvc

Two binary files have been added to the test folder because the "short"
import library format doesn't seem to be creatable via `dlltool`
and requires Microsoft's `lib.exe`.

Reviewers: bgamari, RyanGlScott, erikd, goldfire, austin, hvr

Reviewed By: RyanGlScott, erikd

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D1696

GHC Trac Issues: #11072

8 files changed, 38 insertions, 0 deletions

diff --git a/testsuite/tests/ghci/linking/dyn/Makefile b/testsuite/tests/ghci/linking/dyn/Makefile
index 56e27b13fa..b37fdeaf21 100644
--- a/testsuite/tests/ghci/linking/dyn/Makefile
+++ b/testsuite/tests/ghci/linking/dyn/Makefile
@@ -64,6 +64,22 @@ compile_libAB_dyn:
 	'$(TEST_HC)' $(TEST_HC_OPTS) -ignore-dot-ghci -v0 -o "bin_dyn/$(call EXE,T10955dyn)" -L./bin_dyn -lB -lA T10955dyn.hs -v0
 	LD_LIBRARY_PATH=./bin_dyn ./bin_dyn/$(call EXE,T10955dyn)
 
+.PHONY: compile_libAS_impl_gcc
+compile_libAS_impl_gcc:
+	rm -rf bin_impl_gcc
+	mkdir bin_impl_gcc
+	'$(TEST_HC)' $(MY_TEST_HC_OPTS) -odir "bin_impl_gcc" -shared A.c -o "bin_impl_gcc/$(call DLL,ASimpL)"
+	mv bin_impl_gcc/libASimpL.dll.a bin_impl_gcc/libASx.dll.a
+	echo "main" | '$(TEST_HC)' $(TEST_HC_OPTS) --interactive -ignore-dot-ghci -v0 T11072.hs -lASx -L./bin_impl_gcc
+
+.PHONY: compile_libAS_impl_msvc
+compile_libAS_impl_msvc:
+	rm -rf bin_impl_msvc
+	mkdir bin_impl_msvc
+	'$(TEST_HC)' $(MY_TEST_HC_OPTS) -odir "bin_impl_msvc" -shared A.c -o "bin_impl_msvc/$(call DLL,ASimpL)"
+	rm -f bin_impl_msvc/libAS*.a
+	echo "main" | '$(TEST_HC)' $(TEST_HC_OPTS) --interactive -ignore-dot-ghci -v0 T11072.hs -lAS -L./bin_impl_msvc -L"./$(shell uname -m)"
+
 .PHONY: T1407
 T1407:
 	cat T1407.script | LD_LIBRARY_PATH=. "$(TEST_HC)" $(TEST_HC_OPTS) -ignore-dot-ghci -v0 --interactive -L.
diff --git a/testsuite/tests/ghci/linking/dyn/T11072.hs b/testsuite/tests/ghci/linking/dyn/T11072.hs
new file mode 100644
index 0000000000..56636d809f
--- /dev/null
+++ b/testsuite/tests/ghci/linking/dyn/T11072.hs
@@ -0,0 +1,7 @@
+module Main where
+
+import Foreign
+import Foreign.C.Types
+foreign import ccall "foo" dle :: IO CInt
+
+main = dle >>= print
diff --git a/testsuite/tests/ghci/linking/dyn/T11072gcc.stdout b/testsuite/tests/ghci/linking/dyn/T11072gcc.stdout
new file mode 100644
index 0000000000..78c6baefdd
--- /dev/null
+++ b/testsuite/tests/ghci/linking/dyn/T11072gcc.stdout
@@ -0,0 +1 @@
+2

diff --git a/testsuite/tests/ghci/linking/dyn/T11072msvc.stdout b/testsuite/tests/ghci/linking/dyn/T11072msvc.stdout
new file mode 100644
index 0000000000..78c6baefdd
--- /dev/null
+++ b/testsuite/tests/ghci/linking/dyn/T11072msvc.stdout
@@ -0,0 +1 @@
+2

diff --git a/testsuite/tests/ghci/linking/dyn/all.T b/testsuite/tests/ghci/linking/dyn/all.T
index e1e0fd289e..d54c84eec9 100644
--- a/testsuite/tests/ghci/linking/dyn/all.T
+++ b/testsuite/tests/ghci/linking/dyn/all.T
@@ -34,3 +34,13 @@ test('T10458',
      pre_cmd('$MAKE -s --no-print-directory compile_libT10458'),
      extra_hc_opts('-L$PWD/T10458dir -lAS')],
      ghci_script, ['T10458.script'])
+
+test('T11072gcc',
+     [unless(doing_ghci, skip), unless(opsys('mingw32'), skip), extra_clean(['bin_impl_gcc/*', 'bin_impl_gcc'])],
+     run_command,
+     ['$MAKE -s --no-print-directory compile_libAS_impl_gcc'])
+
+test('T11072msvc',
+     [unless(doing_ghci, skip), unless(opsys('mingw32'), skip), extra_clean(['bin_impl_msvc/*', 'bin_impl_msvc'])],
+     run_command,
+     ['$MAKE -s --no-print-directory compile_libAS_impl_msvc'])
diff --git a/testsuite/tests/ghci/linking/dyn/i686/libAS.lib b/testsuite/tests/ghci/linking/dyn/i686/libAS.lib
new file mode 100644
index 0000000000..3d976ea0df
--- /dev/null
+++ b/testsuite/tests/ghci/linking/dyn/i686/libAS.lib
diff --git a/testsuite/tests/ghci/linking/dyn/libAS.def b/testsuite/tests/ghci/linking/dyn/libAS.def
new file mode 100644
index 0000000000..4873b34ac7
--- /dev/null
+++ b/testsuite/tests/ghci/linking/dyn/libAS.def
@@ -0,0 +1,3 @@
+LIBRARY libASimpL
+EXPORTS
+foo
diff --git a/testsuite/tests/ghci/linking/dyn/x86_64/libAS.lib b/testsuite/tests/ghci/linking/dyn/x86_64/libAS.lib
new file mode 100644
index 0000000000..3b207086fb
--- /dev/null
+++ b/testsuite/tests/ghci/linking/dyn/x86_64/libAS.lib